Dental materials journal最新文献

The longevity of dental restorations is highly dependent on the durability of the resin-dentin interface, where collagen degradation and bacterial infiltration remain key challenges. Lignin, a natural and sustainable polymer, offers antioxidant, cross-linking, and antimicrobial potential, and its combination with silver nanoparticles (AgNPs) could further enhance antibacterial efficacy. This study aimed to investigate the use of lignin and lignin-capped AgNPs (lignin/AgNPs) as bio-based fillers in dental adhesives to improve collagen stability and antibacterial performance. Incorporating 0.5 wt% lignin and 0.5 wt% lignin/AgNPs into dental adhesives significantly improved bond strength, increasing from 15.36 MPa to 22.87 MPa and 27.54 MPa, respectively. FTIR analysis confirmed improved collagen cross-linking. While lignin alone provided limited antibacterial effects, lignin/AgNPs achieved strong activity against Streptococcus mutans. Importantly, both adhesives maintained bond strength after 6-month aging and exhibited no cytotoxicity at clinically relevant concentrations. These findings support their application in the development of advanced dental materials.

The present article describes the fabrication of a bioresorbable, antibacterial bone cement comprising carbonate apatite (CO₃Ap) and gentamicin sulfate (GNT). We focused on a fast-setting CO₃Ap cement using vaterite and monetite as raw powders and Na₂HPO₄ as a mixing solution, to which we added GNT. The initial setting time, physical properties, drug release property, antibacterial property, and in vivo bioresorbability and biocompatibility of the CO₃Ap cements were evaluated. The addition of GNT decreased the initial setting time without affecting the other physical properties of the set cements. Moreover, the GNT-loaded CO₃Ap cements demonstrated potential for drug sustained-release and prevented the growth of Escherichia coli. In vivo studies, the cement formed osteoconductive connections with the bone-like tissues in rat tibia; however, delayed bioresorption was observed. Based on these results, we conclude that GNT-loaded CO₃Ap cements that reduce the risk of surgical site infection are potential candidates for bioabsorbable bone cement.

Surface physical and chemical modifications can effectively enhance implant biocompatibility and soft tissue adhesion. In this study, titanium (Ti) plates were modified by magnetron sputtering to incorporate strontium (Sr), and the effects of Sr-doped Ti materials on fibroblast proliferation and adhesion were systematically evaluated. The results demonstrated that Sr-doped Ti significantly improved L929 fibroblast proliferation, cellular morphology during adhesion, and adhesion strength. Surface characterization by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and atomic force microscopy confirmed the successful incorporation of Sr and revealed changes in surface morphology and potential. RNA sequencing and Western blot analyses showed that Sr enhanced fibroblast adhesion by activating the calcium-sensing receptor (CaSR)/PKC/AKT signaling pathway. Moreover, pharmacological inhibition of CaSR effectively reversed the Sr-induced promotion of fibroblast adhesion and AKT activation. These findings suggest that Sr-functionalized Ti implants can promote fibroblast adhesion and early soft tissue integration, offering a promising strategy to improve implant success rates and prevent peri-implant diseases.

This study aimed to compare the efficacy of tooth whitening and prevalence of tooth sensitivity between 6% hydrogen peroxide (HP) and 10 % carbamide peroxide (CP) at-home whitening systems. Forty-eight patients were chosen and divided into two groups: 6% HP (Tion Take Home With, WI) and 10% CP (Tion Take Home Platinum, PL). Both groups followed the manufacturer's instructions. The whitening procedures were performed over a 10 day period of 1 h per day in WI and a 14 day period of 2 h per day in PL. Tooth color changes were measured with a spectrophotometer. The pain intensity was assessed using a numerical rating scale. No significant differences in ΔE*ab, ΔE₀₀, and ΔW_ID were found between the groups. Tooth sensitivity was more prevalent in WI than in PL. Ten days of 6% HP use was as effective as 14 days of 10% CP.

Since 1982, 4-META/MMA-TBB resin cement (Superbond, Sun Medical, Moriyama, Shiga, Japan; SB) has been applied to preserve root fractures (RFs) in 317 patients (369 roots) treated in our clinic from February 1982 to December 2016, respecting patients' wishes. Follow-up data were collected as of December 31, 2021. The 5- and 10-year survival rates were 92.7% and 65.9%, respectively, with a median survival time of 15.08 years. A multivariate Cox hazard model identified patient age and Masaka's classification (Type M-1: U-shaped RFs treated by intraoral adhesion method) as significant prognostic factors. The hazard ratio for age was 1.022 (95% CI: 1.008-1.037). Type M-1 cases showed a 10-year survival rate of 94.7% with more than half of the treated teeth remaining functional at the time of data collection. These findings suggest that SB can effectively restore and maintain the function of RFs for a decent period.

The objective of this study was to evaluate polyetheretherketone (PEEK) as a post material for resin core abutments in bovine root by static and dynamic fracture loads, with comparison for fiber-reinforced composite (FRC) post. Resin core abutments using experimental PEEK post (CR-PEEK) and bovine root (BRA-PEEK) were fabricated. Specimens including those built-up FRC posts instead of PEEK posts (CR-FRC and BRA-FRC) were also evaluated for load durability under static and dynamic loading tests. CR-PEEK had a lower fracture load than CR-FRC. BRA-PEEK and BRA-FRC had similar static and dynamic loads, with the primary fracture mode involving delamination of the abutment from the tooth structure due to ferrule fracture, with plastic deformation in the experimental PEEK post. In conclusion, experimental PEEK post could be a viable post material for resin core abutment when used in combination with resin composite.

Polyetheretherketone (PEEK) cannot be used without veneering in the anterior area. This study aims to observe the influence of the various surface treatment protocols on the shear bond strength (SBS) between veneering resin composite and PEEK. Sixty cylindrical PEEK specimens (16×5 mm) were fabricated using CAD-CAM, and divided into six groups (n=10) based on the surface treatment method: NT: no treatment (control), SA: 98% sulphuric acid, HP: 30% hydrogen peroxide, SB: airborne particle abrasion with 50 µ aluminum oxide particles, SL: silicatization followed by silanization, and HF: 9.5% hydrofluoric acid. After the application of the resin composite, specimens were thermocycled and subjected to fracture testing using a universal testing machine. Fractured surfaces were examined microscopically and the data were analyzed statistically. The SA and SL groups exhibited significantly higher mean SBS values (p<0.001), although the difference between them was not statistically significant (p=0.24).

This study investigates the correlation between Amide I and III components in dentine's infrared spectrum, focusing on structural changes due to acidic conditioning and adhesive treatments. Human dentine specimens (n=40) were treated with phosphoric acid, phytic acid, and two self-etching adhesives (G-Premio Bond and Adhese Universal), then analyzed using ATR-FTIR spectroscopy. Deconvolution of Amide I and III peaks quantified changes in secondary structures, including α-helices, β-sheets, and β-turns. Results showed strong positive correlations between specific Amide I and III components. The collagen triple helix remained stable after treatment, indicating its potential for normalizing Amide III components. Amide I, however, remains preferred for calculating the mineral-to-matrix ratio due to its higher intensity. The study highlights that Amide III analysis may be more accurate for monitoring structural changes in dentine collagen, avoiding errors from overlapping water vibrations with Amide I.

This study investigated the impact of 1,500 ppm fluoride-containing toothpaste on the surface properties of CAD-CAM resin composites. An accelerated degradation test was performed using five commercial NaF-containing toothpastes, which were applied to two commercial CAD-CAM resin composites and stored under static conditions at 37°C for 14 days without mechanical brushing. The results showed that four toothpastes significantly increased surface roughness and reduced gloss. To further elucidate this phenomenon, a similar accelerated degradation test was conducted using experimental aqueous solutions containing NaF (1,500 ppm) and sodium dodecyl sulfate (SDS; 2 wt%), a common component in the toothpastes that caused the most severe degradation. The findings indicated that SDS accelerates the degradation of CAD-CAM resin composites in the presence of NaF, suggesting that toothpastes containing both NaF and SDS contribute to the deterioration of surface properties.

Bone defects of oral and maxillofacial have always been the difficult problems in clinical treatment. Traditional methods like autografts or allografts bone graft still remain some disadvantages. With the developments of bone tissue engineering, the applications of marine organisms have attracted lots of attention. This research intended to prepare a synergistic pepsin-hydrolyzed tilapia fish collagen (PHFC)/hydroxyapatite (HAP) composite, which based on the components and structure of natural bone extracellular matrix (ECM). Through in vitro and in vivo experiments, we preliminarily demonstrated that this composite exhibits excellent biocompatibility, appropriate degradation rate, and favorable osteogenic properties. In conclusion, this novel material can be regarded as bioactive ingredient for biomaterials used in bone regeneration.